larynx, pharynx, nasal cavity

Question 1

Overview of larynx

Answer 1

• anterior of neck at level C3-C6
• designed for voice production
• connects pharynx with trachea
• guards air passages and maintains a patent airway

Question 2

Skeleton of Larynx

Answer 2

• hyoid bone + 7 cartilages:
  1. thyoid
  2. cricoid
  3. epiglottis
  4. arytenoid (2)
  5. corniculate (2)
• epiglottis folds over opening of larynx during swallowing

Question 3

arytenoid cartilage move in 3 ways:

Answer 3

1. sliding on transverse axis
2. sliding on anteroposterior axis
3. rotating
   - vocal ligaments run from arytenoid cartilages to the thyroid cartilage

Question 4

5 muscles of Larynx

Answer 4

1. cricothyroid
2. posterior cricoarytenoid
3. lateral cricoarytenoid
4. thyroarytenoid
5. transverse and oblique arytenoids

Question 5

function and innvervation of lalryngeal muslces

Answer 5

• function of laryngeal muscles: modulate voice and airflow
• posterior cricoarytenoid is only mm. which ABDUCTs
• innervation: vagus nerve (CNX)
• exernal laryngeal br. of CN X to cricothyroid
• recurrent laryngeal br. CN X to all others

Question 6

injury to recurrent laryngeal nerve

Answer 6

• may be injured due to inflammation or surgery on structures around it in the neck (thyroid gland, trachea, esophagus)
• injury results in high-pitched, noisy respiration and breathy voice

Question 7

The pharynx

Answer 7

• Muscular tube that extends from base of cranium
• to inferior border of cricoid cartilage (anteriorly) and inferior border of C6 (posteriorly)
• conducts air to the larynx, trachea, and lungs (respiratory system)
• part of the digestive system which pushes food into the esophagus

Question 8

parts of pharynx

Answer 8

1. nasopharynx
2. oropharynx
3. laryngopharynx

Question 9

Oropharynx & Laryngppharynx

Answer 9

Oropharynx- communicates with oral cavity, nasopharynx, and laryngopharynx

Laryngopharynx- communicates with larynx (voicebox) and esophagus

Question 10

Muscles of soft palate

Answer 10

1. tensor veli palatini- tenses palate; CN V3 mandibular nerve
2. levator veli palatini- elevates palate; CN X vagus nerve

Question 11

tonsils

Answer 11

• lymphatic tissue
• 4 tonsils form a defensive ring around the naso/oropharynx
• pharyngeal-superior
• palatine- lateral
• tubal-lateral
• lingual- inferior

Question 12

muscles of pharynx external layer

Answer 12

• superior, middle, inferior constrictors
• constrictors wall of pharynx during swallowing
• peristaltic wave
• inferior constrictor muscle blends in with esophagus
• innervated by vagus nerve via pharyngeal plexus

Question 13

muscles of pharynx internal layer

Answer 13

• palatopharyngeus
• salpingopharyngeus
• stylopharyngeus
• elevates pharynx and larynx during swallowing and speaking
• innervated by vagus nerve via pharyngeal plexus
• glossopharyngeal nerve

Question 14

Some innervation rules

Answer 14

1. if tensor :CN V3
2. if palato: CN X (unless rule 1 applies
3. If glosso: CN XII (unless rule 2 applies)

Question 15

Stage I of deglutition

Answer 15

• voluntary
• food bolus pushed against palate via tongue
• bolus squeezed into oropharynx via tongue and soft palate
• tensor veli palatini: tenses soft palate, makes it rigid enough for the tongue to press against
• styloglossus
• palatoglosses: elevate tongue against palate

Question 16

Stage II of deglutition

Answer 16

• involuntary
• soft palate is elevated, sealing off the nasopharynx
• levator veli palatini: elevates the palate
• uvular: elevates the uvula
• palatoglossus: elevates back of tongue to continue pushing bolus down the pharynx
• pharynx is widened and shortened to receive food bolus

Question 17

1. muscles that elevates pharynx

2. muscles that elevates larynx, protract hyoid bone

Answer 17

1. pharynx elevated
   - palatopharyngeus
   - saloingopharyngeus
   - stylopharyngeus
2. hyoid bone protracted, larynx elevated
   - geniohyoid
   - mylohyoid

Question 18

Stage III of deglutition

Answer 18

• involuntary
• sequential contraction of all three constrictor muscles forces food inferiorly into the esophagus
• superior, middle, inferior constrictor
• epiglottis closes the larynx:
  1. pressure of food against the epiglottis
  2. aryepiglottic m
  3. innvervated by vagus nerve

Question 19

bolus moves down esophagus via

Answer 19

peristaltic contraction

Question 20

Gag reflex (pharyngeal reflex

Answer 20

• touching posterior 1/3 of tongue, soft palate, pharynx (general sensation transmitted in IX) elicits reflex
• causes contraction of pharynx muscles (somatic motor innervated by X)
• prevents anything from entering throat, prevents choking; can be used intentionally to produce vomiting

Question 21

lateral wall of nasal cavity

Answer 21

• superior, middle, inferior nasal concha
• increase surface area of nasal cavity
• warms and moistens air as it enters the body

Question 22

nasolacrimal duct

Answer 22

• begins at lacrimal foramen in the lacrimal bone

- ends underneath the inferior nasal concha

Question 23

paranasal sinuses

Answer 23

• air pockets named for the bone that they’re in:
  1. frontal sinus
  2. ethmoid sinus
  3. sphenoid sinus
  4. maxillary sinus
• they are all open to the nasal cavity which is a source of infection
• maxillary sinuses are open behind the middle nasal concha
• sphenoid sinus is open under superior nasal concha
• sinusitis: infection and/or inflammation of any sinuses
• be careful blowing your nose: forcing mucus into sinuses can have negative consequences